ZapperBox Staff - Jan 31 2023
Selecting a Dolby® Receiver for NEXTGENTV
This piece was prompted by a ZapperBox team member who found the Onkyo TX-NR6050 for sale at Costco for $400 and asked if this receiver can handle Dolby Atmos. The Onkyo website is a bit misleading on this issue. It claims that the receiver is 7.2 capable.
First a word about Dolby Atmos: As most readers may already know, Dolby Surround provides two-dimensional audio. This standard was specified for ATSC 1.0 as Dolby AC-3 where AC stands for Audio Codec. Dolby Atmos adds a Z-axis component to the audio experience. The word Atmos is probably a play on “atmosphere”. Dolby Atmos lets you experience sound not just surrounding you but by enveloping the space above and below you, as well. ATSC 3.0 mandates this standard in the USA as Dolby AC-4.
Dolby Surround (AC-3) receivers are specified with two digits, like h.s. Here 'h' specified the number of horizontal speakers that surround you in the XY plane and ‘s’ specifies the number of subwoofers. Dolby Atmos (AC-4) receivers are specified with three digits as h.s.v, where ‘v’ specifies the number of Z-axis (vertical) speakers. Dolby Atmos (AC-4) receivers are backwards compatible with Dolby Surround (AC-3) sound sources.
This is what confused us about the Onkyo TX-NR6050’s claim of supporting Dolby Atmos and yet missing the ‘z’ number. However, a careful reading of the actual spec sheet makes it clear that this receiver can also be deployed in a 5.2.2 configuration (5.1.2 in Zone 1) for true Dolby Atmos. It appears that because Dolby Atmos is still fairly new, manufacturers are calling their systems Dolby Atmos but headlining the number of speakers supported in the old Dolby Surround (h.s) format. You have to dig into the spec sheets to confirm the h.s.v configuration supported.
It is important to note here that the ZapperBox can either decode dual channel Dolby AC-4 or AC-3 locally. Or, it can pass as many as 7.1.4 channels of audio to a connected Dolby receiver. If you are in the market for an ATSC 3.0 tuner, you should ensure that it is certified for Dolby AC-4 audio, which is also backwards compatible with Dolby AC-3 for ATSC 1.0. Without this your ATSC tuner will not be able to process Dolby AC-4 audio locally or even pass it to a Dolby capable receiver to play audio for NEXTGENTV channels.